1. Field of the Invention
The present invention relates to a tool engraving of a deformation tool for deforming with an active medium, wherein the tool exhibits a pressure medium feed line for the active medium and an engraving corresponding to the final contour of the work piece and wherein liquid or gaseous pressure agents are employed as an effective medium.
2. Brief Description of the Background of the Invention Including Prior Art
The deformation of the wall of the work piece relative to the engraving of the tool is performed by the pressure of the pressure medium in connection with the generic deformation methods in case of hydrodeforming (compare for example German printed patent document DE 4434799 A1) as well as in case of internal high-pressure deforming (compare for example German printed patent document DE 19535870 A1 and A. Notrott: Neuere Entwicklungen in der Blechumformung; K. Siegert: Neuere Entwicklungen beim Innenhochdruckumformen . . . , 1998, Publisher MAT-INFO Werkstoffinformationsgesellschaft mbH, S. 365-367). During removal of the work piece, the pressure medium can pass to the engraving of the tool, whereby no contact between engraving and wall of the work piece occurs during metal forming of the following workpieces in that region, where the pressure agent adheres to the engraving, whereby undesired deformations occur at the tool piece. These deformations cause limitations in the evaluation of the surface quality of the work piece. Bubble formations between sheet metal or thin foils to be deformed and the engraving can occur also in connection with gaseous active media, whereby again undesirable deformations of the workpieces are generated.